The Ledger
Every statement that passed quotation and attribution checks. Mix any filter with any other: certainty 1/5, debate potential 5/5, or both at once.
why aren't all 37 resolved? a statement only gets an assessment when the public record can support or contradict it. opinions and what-ifs never can, and 1 checkable ones are still open, waiting for their date. predictions held up or didn't; assertions are supported or contradicted. on every card: ▮▮▮▮▮ certainty · ▮▮▮▮▮ debate potential. speakers are clickable
Klein: AI agents will use existing web interfaces instead of rebuilding APIs
“The thing that's hard is like reinventing the internet for agents. We don't want to rebuild the internet. That's an impossible task. And I think people often say like, well, we'll have this second layer of APIs built for agents. I'm like, we will for the top u…”
Klein: OpenAI's brand constraints will prevent them from offering CAPTCHA solving
“I think it's going to be really hard for a company like OpenAI to do things like support CAPTCHA solving or like have proxies. Like, I think it's hard for them structurally. Imagine this New York Times headline, OpenAI CAPTCHA solving. Like, that would be a pr…”
Klein: Browserbase delivers 90% of computer-use functionality at 10% of OS cost
“BrowserBase can run browsers for way cheaper than you can if you're running a full-fledged OS with a GUI, you know, operating system. And I think that's just an advantage of the browser. It is like, browsers are like little OSs, and you can run them very effic…”
Klein: Browserbase will be a billion-dollar company within five years
“I can predict that Browserbase will be a billion dollar company one day. So let's check back in five years.”
Klein: Vision models, not HTML text parsing, drive computer use AI
“Maybe my hot take is like, I was always kind of like, I didn't think vision would be as big of a driver for UI automation. I felt like, you know, HTML is structured text and large language models are good with structured texts, but It's clear that these comput…”
Klein: Browserbase's PE-backed rival hasn't updated its dashboard in five years
“Our biggest competitor actually is partly owned by private equity, and they just jacked up their prices quite a bit, and the dashboard hasn't changed in five years”
Klein: Infrastructure startups require deeper control than managed services like Fargate provide
“And unfortunately it just, it's a great product, but I think if you're an infrastructure company, you actually have to have a deeper level of control over these primitives. I think it's the same thing is true with databases.”
Klein: Purchasing commercial web proxies online feels like buying illicit drugs
“It's like you're buying drugs when you're trying to get a proxy online.”
Klein: Authentication, not CAPTCHAs, will be the biggest barrier for AI agents
“I actually think that off is the biggest thing that will prevent agents from accessing stuff, not captures.”
Klein: There are no genuinely good generic AI agent frameworks
“I don't think I've seen a generic, and maybe you guys are the experts here, I haven't seen like a really good AI agent Framework here. Everyone kind of has their own special sauce, right?”
Klein: DOM-anchored agent actions are more reliable than vision-based coordinate clicking
“I think that using mouse click or mouse coordinates, I've seen that proved to be less reliable than I would like. And I just wonder if that's the right form factor. What we've done with our framework is Anchor it to the DOM itself. Anchor it to the actual item…”
Klein: Complex developer primitives like web browsers require bespoke, dedicated infrastructure
“For tools and primitives with sufficient levels of complexity, you need to have a solution that's really bespoke to that primitive, you know, and I am sufficiently convinced that the browser is complex enough to deserve a primitive.”
Klein: Having co-founders slows startup execution by adding an extra alignment layer
“If you want to move extremely fast as a company, one of the hard parts about having co-founders is that there's like, you have to do the co-founder alignment and then the company alignment. And then there's people on the team that probably tell things to one c…”
Klein: Polarizing binary decisions make maintaining company culture easier to assimilate
“When you make people make a polarizing decision of like, I will come to an office five days a week, people then end up making more decisions that are aligned with the culture. So it's almost like if you can make your culture binary or you're in or out, It beco…”
Klein: Cloud browsers require stateful containers, not serverless Lambdas
“So if you want to run a web browser or thousands of web browsers, you can't just spin up a bunch of Lambdas. You actually need to use a secure containerized environment. You have to scale it up and down. It's a stateful system.”
Klein: Browserbase spent zero dollars on AI in its AI Grant batch
“I'm in AI grant, you know, browsers was an AI grant, but we were the only company in that AI grant batch that used zero dollars on AI spend.”
Klein: Headless browsers are a core primitive for future LLM operating systems
“Browsers are a core primitive of infrastructure for the LLMOS that's going to exist in the future”
Klein: Developer tools founders should partner with consumer-focused design agencies
“I highly recommend for developer tools founders to work with consumer agencies because they end up building beautiful things and the Parisians know how to build beautiful interfaces.”
Klein: Developers evaluate tools by design polish and trust in the founder
“As a developer, you think you evaluate a company based on like the API reliability and the P-ninety-five, but a lot of developers say, is the website good? Is the message clear? Do I like trust this founder I'm building my whole feature on?”
Klein: Stateful distributed browser systems are painful to run and maintain
“Those are some of the worst systems to run because when it's a stateful distributed system, it means that you are bound by the connections to that thing. You have to keep the browser open while someone is working with it, right? That's just a painful architect…”
Klein: Browserbase briefly became the largest regional Fargate customer before moving lower-level
“We used to be a giant Fargate customer. Actually, the first version of BrowserBase was ECS and Fargate. And I unfortunately it's a great product. I think we were actually the largest Fargate customer in our region for a little while.”
Klein: Authentication providers will offer dedicated login features for AI agents
“I think there'll be agent off in the future. I don't know if it's going to happen from an individual company, but actually authentication providers that have a You know, hidden login as agent feature, which will then you put in your email. You'll get a push no…”
Klein: OpenAI Operator uses VNC rather than Chrome DevTools Protocol
“Operator actually uses a different approach. They use VNC.”
Klein: Web agents still require human-in-the-loop workflows for CAPTCHAs and 2FA
“Web agents need human the loop type workflows still. You still need a person to interact with a browser and building a UI to proxy that is kind of hard. You may as well just show them the whole browser and say, Hey, can you finish this up for me? And then let …”
Klein: Consumer AI agents and tools like Anthropic MCP will run locally
“There's a case where a lot of people are going desktop first for, you know, consumer use. And I think Claude is doing a lot of this where I expect to see, you know, MCP is really oriented around the Claude desktop app for a reason, right? Like I think a lot of…”
Klein: AI apps requiring browser interactions need dedicated backend cloud infrastructure
“If you're building applications that rely on a browser and it's more part of a greater like AI app experience, you probably need something that's more like infrastructure, not a consumer app.”
Klein: Agent loops belong at the application layer, making Stagehand a framework
“Stagehand isn't a web agent. It's a framework for building web agents. And we think that agent loops are actually pretty close to the application layer because every application probably has different goals or different ways it wants to take steps.”
Klein: Stagehand is built for AI agent reliability, not dedicated web scraping
“If you're building a scraping company, StageChan's not your thing. You probably want something that's gonna, like, get HTML content, you know, convert that to Markdown, query it. That's not what StageChan does. StageChan's more, more about reliability.”
Klein: Web scraping workflows should use a tiered waterfall architecture
“If you're building web scraping workflows, what you should do is have a waterfall. You should have the first request is a curl to the website. See if you can get it without even using a browser. And then the second request may be like a scraping specific API. …”
Klein: The future of software is software operating other software autonomously
“The future of software is software using software.”
Klein: Browserbase operates fully in-person Monday to Friday from 10 to 6
“Culturally, like we're fully in-person. Maybe that's one crazy take that we do, but we're also like not too in-person. Like our first meeting's at 10 a.m. People leave around five or six. We work Monday to Friday in-person, and those like, that's the expectati…”
Klein: Former YC CTOs and ex-founders make the best early startup hires
“Culturally, we're a lot of like former YCCTOs and like ex-founders or future founders. And I've just found that those people tend to be just really great early hires for a company. They get it.”
Klein: Automating niche local public records extraction offers high-alpha investment signals
“There's so much money to be made in taking like proprietary research and then turning that into like an automation, which is obviously like a very like browser based inspired one, like listening to all of the city halls or town hall meetings in like little tow…”
Klein: Browserbase grew to 20 people and Series A in year one
“Like, BrowserBase is actually pretty close to our first birthday, so we are one years old, and going from, you know, Starting a company as a solo founder to, you know, having a team of 20 people, you know, a series A, but also being able to support hundreds of…”
Klein: Founders from Stytch, Clerk, and Okta Ventures invested in Browserbase
“And, you know, three from Stitch is an investor, Colin from Clark. Okta Ventures, all investors in BrowserBase because like, I hope they solve this because it'll make BrowserBase's mission more possible.”